Automated AI-enabled CT Biomarkers for Population-Based Opportunistic Detection of Patients at Risk for Unsuspected Advanced Hepatic Fibrosis and Cirrhosis

Author

Lu Mao

Published

May 16, 2025

Statistical analysis

Categorical variables were summarized as counts and percentages, and continuous variables were summarized as median (interquartile range) and range. The Kruskal-Wallis rank sum test was used to compare continuous variables across groups. The Spearman rank correlation coefficient was calculated to assess the correlation between FIB-4 and age. The significance level was set at 0.05. All statistical analyses were performed using R version 4.2.2 (R Foundation for Statistical Computing, Vienna, Austria).

Patient characteristics

Patient characteristics are summarized in Table 1.

Table 1: Patient characteristics
Characteristic Overall, N = 31,2891 F, N = 16,6261 M, N = 14,6631
Age (years) 52 (45, 58) 52 (44, 58) 53 (46, 59)
FIB-4 0.94 (0.65, 1.48) 0.86 (0.60, 1.28) 1.05 (0.72, 1.74)
FIB-4 Category


    Low Risk (< 1.3) 21,771 (70%) 12,572 (76%) 9,199 (63%)
    Intermediate Risk (1.3-2.67) 5,759 (18%) 2,563 (15%) 3,196 (22%)
    High Risk (≥2.67) 3,759 (12%) 1,491 (9.0%) 2,268 (15%)
LSVR 0.30 (0.25, 0.36) 0.31 (0.26, 0.37) 0.28 (0.23, 0.34)
LSVR Category


    LSVR<.347 22,212 (71%) 10,999 (66%) 11,213 (76%)
    LSVR≥.347 9,077 (29%) 5,627 (34%) 3,450 (24%)
Spleen Volume (mL) 247 (170, 365) 209 (150, 300) 299 (208, 438)
Spleen Volume Category


    SV<315 mL 20,779 (66%) 12,921 (78%) 7,858 (54%)
    SV≥315 mL 10,510 (34%) 3,705 (22%) 6,805 (46%)
1 Median (IQR); n (%)

FIB-4 distribution across LSVR and SV groups

Table 2 and Figure 1 show the distribution of FIB-4 score across LSVR and SV groups by sex.

Table 2: FIB-4 distribution across LSVR and SV groups by sex
Characteristic LSVR<.347, SV<315 mL, N = 14,8761 LSVR≥.347, SV<315 mL, N = 5,9031 LSVR<.347, SV≥315 mL, N = 7,3361 LSVR≥.347, SV≥315 mL, N = 3,1741 p-value2
Overall 0.86 (0.61, 1.22) 0.89 (0.62, 1.28) 1.07 (0.70, 1.83) 2.08 (0.94, 5.21) <0.001
1 Median (IQR)
2 Kruskal-Wallis rank sum test
Characteristic LSVR<.347, SV<315 mL, N = 8,6631 LSVR≥.347, SV<315 mL, N = 4,2581 LSVR<.347, SV≥315 mL, N = 2,3361 LSVR≥.347, SV≥315 mL, N = 1,3691 p-value2
Female 0.82 (0.58, 1.15) 0.84 (0.59, 1.21) 0.97 (0.62, 1.67) 1.64 (0.80, 4.66) <0.001
1 Median (IQR)
2 Kruskal-Wallis rank sum test
Characteristic LSVR<.347, SV<315 mL, N = 6,2131 LSVR≥.347, SV<315 mL, N = 1,6451 LSVR<.347, SV≥315 mL, N = 5,0001 LSVR≥.347, SV≥315 mL, N = 1,8051 p-value2
Male 0.93 (0.66, 1.32) 1.02 (0.72, 1.58) 1.11 (0.75, 1.91) 2.47 (1.08, 5.61) <0.001
1 Median (IQR)
2 Kruskal-Wallis rank sum test
Figure 1: Boxplots of FIB-4 distribution across LSVR and SV groups by sex

FIB-4 vs age

Relationship between FIB-4 and age is plotted in Figure 2, which shows a general correlation in each sex and overall.

Figure 2: Correlation between FIB-4 and age by sex